Attorney General William Barr’s management of Robert Mueller’s Trump-Russia report has drawn widespread criticism—including, as it turns out, by the man himself. Following reports that Mueller's staff disagreed with how Barr characterized Mueller’s report in an initial four-page summary—and the Democratic outcry against Barr after the report’s release—the Washington Post and New York Times reported Tuesday that Mueller, too, took issue with how Barr decided to sum up his much-hyped investigation.

According to the reports, Mueller wrote a letter to Barr after the four-page summary of Mueller’s report came out, in which the special counsel said the summary “did not fully capture the context, nature, and substance” of the full 400-page report. “There is now public confusion about critical aspects of the results of our investigation,” Mueller wrote. “This threatens to undermine a central purpose for which the Department appointed the Special Counsel: to assure full public confidence in the outcome of the investigations.” The four-page memo, which Barr said Mueller declined to review before its release, has been criticized for cherry-picking quotes to come across as more favorable to Trump. The A.G. quoted Mueller in saying that his investigation “did not establish that members of the Trump campaign conspired or coordinated with the Russian government,” for instance—but left out Mueller saying just before that “the investigation established that the Russian government perceived it would benefit from a Trump presidency and worked to secure that outcome, and that the campaign expected it would benefit electorally from information stolen and released through Russian efforts.”

In an effort to clear things up and actually show the public what his two-year-long investigation had produced, Mueller requested in the letter that Barr release the report’s introductions and executive summaries. Barr, of course, declined to do so, which a Department of Justice spokeswoman Tuesday claimed was because “it would not be productive to release the report in piecemeal fashion.” The letter was also followed by what the D.O.J. statement described as a “cordial and professional” phone conversation, in which Mueller “emphasized that nothing in the Attorney General’s March 24 letter was inaccurate or misleading,” but “expressed frustration over the lack of context and the resulting media coverage regarding the Special Counsel’s obstruction analysis.” A spokesman for the special counsel’s office declined to comment to the Times about their report.

The news of Mueller’s letter comes at an inconvenient time for Barr, who’s already set to testify before Congress about the Mueller report on Wednesday and Thursday. The lead-up to the hearings has been fraught as it is, with the A.G. vigorously protesting House Democrats’ decision to have staff lawyers question him, but Democrats’ outrage over Mueller’s letter ensures that the hearings are likely to be even more explosive—and potentially damaging to Barr—than previously thought. House Judiciary Chair Rep. Jerrold Nadlersaid Tuesday he’s requested a copy of Mueller’s letter by Wednesday morning, and “note[d] with interest” on Twitter that Barr had previously testified to the Senate that he didn’t know whether Mueller supported his summary’s conclusion. Congress may also be hearing from Mueller himself soon, as the reports of his letter have made his congressional testimony a more urgent priority for House Democrats. Sources cited by NBC suggest lawmakers will push for Mueller to testify by next week, though lawmakers said the Department of Justice has previously been unwilling to set a date for the testimony. “The Attorney General should not have taken it upon himself to describe the Special Counsel’s findings in a light more favorable to the President,” Nadler said in a statement. ”It was only a matter of time before the facts caught up to him.”